Grind oats and bunny pellets into a flour-like consistency (I use a cheap blade-style coffee grinder). Puree banana, carrot, parsley and water in a blender or food-processor (if you're using a blender, start with the carrot and water, adding the parsley in small batches, finishing with the banana).

Mix all together in a medium bowl until a sticky dough forms. Roll out dough between waxed paper to 1/8"-1/4" thickness. Slice into small squares, about 1/2" on a side.

Bake on a parchment covered baking stone (or similar) for 30 minutes, checking to make sure they're not browning too much. Then turn off the heat, and let sit in the oven for an hour, until very dry. Keep in a little canister or resealable container, away from moisture.